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191.
J. M. Evans A. C. Wilkie J. Burkhardt 《Journal of Agricultural and Environmental Ethics》2009,22(2):169-180
Our recent paper advocating adaptive management of invasive nonnative species (INS) in Kings Bay, Florida received detailed
responses from both Daniel Simberloff, a prominent invasion biologist, and Mark Sagoff, a prominent critic of invasion biology.
Simberloff offers several significant lines of criticism that compel detailed rebuttals, and, as such, most of this reply
is dedicated to this purpose. Ultimately, we find it quite significant that Simberloff, despite his other stated objections
to our paper, apparently agrees with our argument that proposals for alternative management of established INS (i.e., alternatives
to minimization/eradication) should not be rejected on an a␣priori basis. We argue that more specific development and application
of adaptive approaches toward INS management, whether in Kings Bay or other appropriate case studies, would be facilitated
if ecosystem managers and invasion biologists follow Simberloff’s lead on this key point. While Sagoff largely shares (and,
indeed, served as a primary source for developing) our general arguments that challenge common moral and scientific assumptions
associated with invasion biology, he does question our suggestion that participatory adaptive management provides an appropriate
framework for approaching environmental problems in which science and politics are inherently entangled. We attempt to answer
this criticism through a brief sketch of what participatory adaptive management might look like for Kings Bay and how such
an approach would differ from past management approaches. 相似文献
192.
Spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments from Daya Bay, South China 总被引:2,自引:0,他引:2
Wen Yan Jisong Chi Weixia Huang 《Environmental pollution (Barking, Essex : 1987)》2009,157(6):1823-1830
The spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) has been investigated in Daya Bay, China. The total concentration of the 16 USEPA priority PAHs in surface sediments ranged from 42.5 to 158.2 ng/g dry weight with a mean concentration of 126.2 ng/g. The spatial distribution of PAHs was site-specific and combustion processes were the main source of PAHs in the surface sediments. Total 16 priority PAH concentration in the cores 8 and 10 ranged from 77.4 to 305.7 ng/g and from 118.1 to 319.9 ng/g respectively. The variation of the 16 PAH concentrations in both cores followed the economic development in China very well and was also influenced by input pathways. Some of the PAHs were petrogenic in core 8 while pyrolytic source was dominant in core 10. In addition, pyrolytic PAHs in both cores were mainly from the coal and/or grass and wood combustion. 相似文献
193.
辽东湾是典型的复杂二类水体,我们利用2002~2004年在辽东湾现场实测的叶绿素a数据(分光法、荧光法和HPLC法),以及水面之上法现场实测的离水辐射率和遥感反射率数据模拟的MODIS各相应波段值对MODIS海洋水色算法进行了评估.评估的MODIS生物光学算法有四个,即CZCS_pigm、chlor_MODIS、chlor_a_2和chlor_a_3算法.结果表明,两个一类水体生物光学算法(CZCS_pigm和chlor_MODIS)反演值与分光法和荧光法测试分析结果相比,算法均低估了叶绿素a浓度,与HPLC分析结果相比算法高估了叶绿素a浓度;两个二类水体算法(chlor_a_2和chlor_a_3)与所有叶绿素a分析方法相比,均高估了叶绿素a浓度.根据MODIS生物光学算法在辽东湾的具体表现,我们认为HPLC法分析的叶绿素a浓度更适合于作为海洋水色算法评估的现场检验依据.叶绿素a浓度的反演值和实测值之间较低的相关系数则显示MODIS两个一类水体算法所采用的波段比值不适合本海区. 相似文献
194.
根据青岛市胶州湾周边的水文地质条件及地下水位、水质动态特征,运用断面法计算了2001~2003年该区地下水及其N、P、Si无机营养盐向海湾的输送量.研究表明近年该区地下水向海湾的输送量分别为(1.87~2.41)×106m3,其中白沙河平原输送量占95%以上.地下水向海湾的NO 2、NH 4、PO3-4输送量较少,而NO 3和可溶性SiO2的输送量较大,分别达(4.3~6.6)×106 mol/a、(0.6~1.1)×106 mol/a,分别占河流输送量的20%和1.3%,白沙河平原地下水NO 3输送量占研究区地下水总输送量的99%. 相似文献
195.
196.
渤海湾海域生态环境的研究Ⅱ.水体富营养化的评价与分析 总被引:3,自引:0,他引:3
根据2003年7月15日、2003年11月4日、2004年2月29日和2004年5月25日在渤海湾多项生态因子的调查结果,应用单因子法和综合指数法对该海域海水的质量状况进行了评价与分析,并与历史资料进行了比较.结果表明,渤海湾水体整体呈现富营养化,主要为无机氮严重超标;另外,春季水体有机污染较为严重,秋季无机磷含量也达到富营养水平.无机氮、无机磷、COD以及营养状态指数(EI)的时空分布大体呈现北高南底,近岸大于外海的趋势,分布趋势与历史资料基本吻合,但比历史同期无机氮、COD浓度增加,水体富营养状态呈现愈发严重的趋势. 相似文献
197.
Vertical distribution of nonylphenol and nonylphenol ethoxylates in sedimentary core from the Beipaiming Channel, North China 总被引:1,自引:0,他引:1
The vertical profiles of nonylphenol (NP) and nonylphenol ethoxylates (NPEOs) were investigated in a sediment core from the Beipaiming Channel, North China using high sensitive LC-MS and GC-MS metthods In this core, relatively high concentrations of NP and NPEOs occurred in the surface sediment (≤40 cm), with the maximum value of NP and NPEOs reaching 3539 and 12735 mg/g, respectively, whereas, no NP or NPEOs were detected in deeper sediments (〉40 cm). The high concentrations of NP and NPEOs in the surface layers suggested recent inputs in this area. NPEOs with short ethoxy chains (NPnEO, n=0-3) were dominant in the NPEO mixture with percentages from 54% to 78%, which were similar to the distribution of homolog NPEO in effluents from nearby sewage treatment plants (STPs), indicating that the channel received the effluents from these STPs. The sewage treatment ratio was quite similar to that found in North America before the 1980s. Finally, the concentrations of NP and NPEOs were related to the total organic carbon (TOC) (p〈0.001), suggesting that TOC was an important factor for vertical distribution of NPEOs and NP from the Beipaiming Channel. 相似文献
198.
Marine Protected Areas (MPAs) have been hailed worldwide as vehicles toward sustainable development (SD) in coastal zones.
The prominent model by which MPAs operate is through a comanagement approach, a shift from traditional top-down management.
This paradigm shift must be reviewed continuously to evaluate its social and ecological impacts, thereby allowing adaptive
management. We evaluated the perceived impacts of the Cogtong Bay Mangrove Rehabilitation Project (CBMRP; Philippines) by
using 12 perception indicators categorized into 3 comanagement impact criteria (equity, efficiency, and sustainability). We
also collected 16 contextual attributes of each respondent to determine the correlates of perceived impacts. Our results showed
that there were significant improvements in all indicators under the efficiency criterion but mixed impacts in the equity
and sustainability criteria. Access to resource and household income (equity) and fisheries abundance (sustainability) were
perceived to have decreased during the last 15 years and were not expected to improve in the future. Stepwise multiple regression
analysis showed that the asymmetries of the perceived impacts of the CBMRP were principally caused by disparities in perceptions
by gender and by location (Candijay and Mabini). This highlighted the importance of cross-scale institutional linkages between
Cogtong Bay municipalities to systematically address baywide management issues. Our results further demonstrated the necessity
of integrating gender issues into the evaluation of MPA impacts to ensure a robust evaluation. Finally, we recommend that
a rigorous evaluation of MPAs using a common set of impact indicators should be encouraged to allow comparison of studies
both spatially and temporally. 相似文献
199.
González-Macías C Schifter I Lluch-Cota DB Méndez-Rodríguez L Hernández-Vázquez S 《Environmental monitoring and assessment》2007,133(1-3):187-207
Concentrations of total aromatic hydrocarbons and extractable organic matter in the water column and sediment were determined
in samples collected in the course of the last 20 years from the Salina Cruz Harbor, México, to assess the degree of organic
contamination. In sediments, organic compounds accumulate in shallow areas mostly associated with extractable organic matter
and fine fractions. Calculated geocumulation index and enrichment factors suggest that contamination could be derived from
anthropogenic activities attributed to harbor and ship scrapping activities, as well as transboundary source. Concentration
of total aromatic hydrocarbons (as chrysene equivalents) ranged from 0.01 to 534 μg l−1 in water, and from 0.10 to 2,160 μg g−1 in sediments. Total aromatic concentration of 5 μg g−1 is proposed as background concentration. 相似文献
200.
Guiling?L.?ZhangEmail author Jing?Zhang Jie?Xu Jingling?L.?Ren Sumei?M.?Liu 《Water, Air, & Soil Pollution: Focus》2007,7(6):645-654
CH4 concentrations in both the surface and bottom waters of Jiaozhou Bay were determined during four surveys in 2003, which showed
variability with both seasons and tidal cycles. Atmospheric fluxes of CH4 in Jiaozhou Bay showed obvious seasonal and spatial variations, with the highest values occurring in summer and the lowest
in winter. The annual emission of CH4 from Jiaozhou Bay was estimated to be . CH4 in the water column of Jiaozhou Bay was found to come from several land-sources including riverine water input, sewage water
input and groundwater input. The spatial and temporal variation in distributions and atmospheric fluxes of CH4 in Jiaozhou Bay was influenced mainly by the input of polluted river waters and the sewage effluents along the eastern coast,
which highlights the effects of human impacts on CH4 emission rates. 相似文献